Apparatus for plating articles and method of making same



3 Sheets-Sheet 1 APPARATUS FOR FLATING ARTICLES AND METHOD OF MAKING SAME Oct. 18, 1960 Original Filed Aug. 10. 195

v INV'ENTUII l dj/05%'.

R. A. HOEGH Oct. 18, 1960 APPARATUS FOR PLATING ARTICLES AND METHOD OF MAKING SAME s sheets-sheet 2 Original Filed Aug. 10, 1953 oct. 1s, 1960 R. A. HOEGH' 2,956,943

APPARATUS FOR PLATING ARTICLES AND METHOD oF MAKING SAME original Filed Aug. 1o, 195s 3 Sheets-Sheet 3 filiali/Ilz V 204 E15 a u I 56 Z 35E T im MNT .J4

ZIE 5' ZEE 14 I i l' f 2,956,943 Ice Patented Oct.` 18, 196,0

APPARATUS FOR PLATING ARTICLES AND METHOD OF MAKING SAME Roy A. Hoegh, Chicago, Ill., assigner to Mercil Plating Equipment Company, Chicago, Ill., a corporation of Illinois Continuation of application Ser. No. 373,136, Aug. 10, 1953. This application Nov. 29, 1957, Ser. No. 700,260

9 Claims. (Cl. 21M-213)' The present invention relates to a novel Iapparatus for treating articles, and more particularly to a novel apparatus of the type, wherein the yarticles to be treated are disposed within a tumbling barrel.

An object of the present invention is to provide an apparatus of the above described type including a novel tumbling barrel constructed of plastic material, which barrel is of simple construction and may be relatively easily and economically manufactured.

Another object of the present invention is to provide a novel tumbling barrel of the above described general type which is constructed in a manner so that upon ro tation thereof in one direction, articles will be discharged therefrom, while during rotation in the opposite direction, articles will be retained therein and efficiently tumbled for proper treatment or plating.

Still another object of the present invention is to provide a novel unit including a tumbling barrel of the above described type, which unit includes means for rotating the barrel, whereby the unit may be used in connection with various treating or plating baths without necessitating connecting and disconnecting the unit with outside sources of power.

Still another object of the present invention is to pro- -vide a novel apparatus, whereby articles may be placed into the barrel, treated, and discharged from the barrel automatically, thereby assuring substantial savings intime and labor costs.

Still a further object of the present invention is to provide a novel method for manufacturing a tumbling barrel of the above described type.

Other objects and advantages of the present invention will become apparent from the following description and the accompanying drawings, wherein:

Fig. 1 is a side elevational View of a novel article treating unit embodying the principles of this invention;

Figs. 2 and 3 are somewhat schematic views illustrating the novel method of forming the sidewall of the barrel of this invention;

Figs. 4 and 5 are somewhat schematic views illustrating, respectively, the manner of loading and unloading the novel barrel of this invention;

Fig. 6 is a cross sectional view taken along line 6--6 in Fig. 7;

Fig. 7 is a cross sectional view taken along line 7-7 in Fig. 6;

Fig. `13 is an enlarged fragmentary cross sectional view- .increases the size of the barrel.

taken along the same line as Fig. 12 and showing a portion of the apparatus in greater detail; and

Fig. 14 is a schematic plan view of the apparatus shown in Fig. 1l.

Referring now more specifically to the drawings, wherein like parts are designated by the same numerals throughout the various gures, a unit 16 for electro-plating articles embodying the principles of this invention is illustrated best in Fig. l. The unit 16 includes a platform or frame 18 which is adapted to be supported or suspended by a hook 20. A pair of hanger arms 22 and 24 ldepend from the platform 18 and support therebetween a novel tumbling barrel 26 embodying certain features of this invention.

In order to rotate the barrel 26 without necessitating setting up driving means every time the barrel is immersed in a plating tank, an electric motor 28 is mounted on the frame or platform 18. A suitable gear chain is provided in order to obtain a driving connection between the motor 2S and the barrel. This gear chain includes a large gear 30 secured to one end of the barrel and a relatively small pinion 32 mounted on the motor shaft. A plurality of idler gears 34 and 36 are mounted on the unit frame by suitable means for connecting the large gear 30 and the pinion 32.

Referring now to Figs. 6 through 10, it will be seen that the novel tumbling barrel 26 includes a pair of end plates 38 and 40 and a generally annularly arranged foraminous side wall 42 secured between said end plates. In accordance with a feature of this invention, the side Wall 42 is arranged to provide a permanent opening 44 through which articles are loaded into or discharged from the barrel. In addition, the side lwall `42 is formed so .that the articles are retained within the barrel when it is rotated in one direction and efiiciently tumble so that an even treatment or coating of the articles is assured. Furthermore, the side wall 42 is formed so that by rotating the barrel in an opposite direction, the articles will be automatically discharged therefrom. The formation of the side wall 42 to accomplish these results is shown best in Fig. 7, wherein the sidewall is illustrated as having a plurality of angularly disposed panels 46, 48, and 50 generally opposite the opening 44 and generally arcuate or curved sections S2 and 54 adjacent the opening. The curved section 54 merges with a relatively sharply in- Wardly curved section 56 which in turn merges with a section 58 extending inwardly of the barrel. In the particular position shown in Fig. 7, it is noted that the portion 58 extends across the vertical axis of the barrel to a point adjacent the horizontal axis of the barrel, whereby the portion 58 is spaced radially inwardly of and in overlapping relationship with respect to the curved portion 52. With this arrangement, when the barrel is rotated in the direction of the arrow 60, articles in the barrel will be retained therein, and when the Kbarrel is rotated in the opposite direction, articles will be `discharged therefrom. When the barrel is rotated in the direction of the arrow 60, the articles to be treated are caught in a pocket for-med -by the curved sections 54 and 56 and the portion 58, and in order to prevent the articles from bouncing out of this pocket and out of the barrel when the barrel is inverted, it has been found desirable to form these pocket forming wall sections in the manner substantially as illustrated. Thus, the start of the relatively sharply curved section 56 is located at substantially the midportion of the upper lefthand quadrant of the barrel when Viewed as in Fig. 7, whereby the above mentioned pocket is provided with ample depth to retain the articles. It will be understood that the sharply curved section 56 may be started at a higher point in the upper lefthand quadrant of the barrel, but this is undesirable since it unnecessarily Vby short arcuate corner sections, which rounded corners prevent jamming of the articles and further strengthen the barrel structure.

In order to prevent coating or plating of any portion of the barrel and its associated structure which will contact the plating bath, the barrel and such associated structure are preferably made of a plastic material. Iu addition, the sidewall 42 is preferably made from a plastic material which may be easily formed finto the shape described above. One such plastic material which has been found satisfactory is a methyl methacrylate resin cast in sheets and sold under the name of Plexiglas As shown best in Fig. 8, the side 42 is joined to the end plate 40 by a plurality of screws 62, which screws are disposed with their heads countersunk in suitable bores in the end plate. In order to prevent plating of the screws, the heads thereof are covered with suitable plastic plugs 64. In addition, the junction between the end plate and the side 42 is sealed with a suitable plastic adhesive. It is, of course, understood that thescrews 62 are spaced evenly around the entire sidewall and that the sidewall is connected to the end plate 3S in the same manner as it is connected to the end plate dit).

In order to reinforce the free longitudinal edge of the curved section 52 of the sidewall, a plastic bar-like member 66 is secured thereto by a suitable adhesive, which bar-like member is also secured to the end plates by countersunk and covered screws 68 and a suitable adhesive. Preferably, the inner wall 70 of the bar 66 is inclined, as illustrated in Fig. 7, to eliminate substantially any possibility of articles being caught and retained by the bar when the barrel is rotated in a direction to discharge the articles. A similar bar-like member 72 is secured to the free edge of the side wall section 5'8 to reinforce this sidewall section.

Since the sidewall 42 is made from plastic material, it is often desirable to provide means for maintaining the desired shape of the angularly disposed panels. This means includes plastic blocks '74, A76, and 78 secured to the end plate 40 and having inclined surfaces abutting the inclined sections of each panel to maintain these sections in the desired position.

As shown best in Fig. 6, the hanger members 22 and 24, which may be made of any suitable material such as wood or plastic, are provided with aligned hollow stub shafts or hubs 80 and 82, respectively. Each of the end plates 3S and 40 is provided with bearing sleeves 84 and 86, respectively, rotatably kreceived on the stub shafts. In addition, the above described large gear 30 encircles the stub shaft 82 and is rigidly secured to the end plate 40 by means of a plurality of countersunk screws 88. The gear 30 is preferably spaced slightly from` the end plate 40 by spacing members 96 which encircle the screws 88 and are secured to the end plate and gear by suitable adhesive, whereby the Shanks of the screws "8S are sealed from contact with the plating bath. The heads .of the screws 88 are also sealed from the plating bath by means of suitable plastic plugs 92.

As shown in Fig. l, a pair of electrodes 94 and 96 are inserted into the tumbling barrel through the hollow stub shafts Sib and 82. Each of the electrodes includes a flexible plastic insulating tube 98 which is secured in and supported by its respective stub shaft and a metaltip 100. It is understood that the flexible plastic tube 98 .houses an electric conduit connected with the metal tip,

bath from where the electrical conduit is directed to any suitable source of electric power.

From the above description, it is seen that the present invention has provided a novel plating barrel and associated structure which is completely free of exposed metal parts, except for the metal tips `of the electrodes, whereby loss ofthe plating metal is eliminated. Furthermore, it is seen that the novel plating barrel is of simple, yet rugged, construction and is formed so as to tumble eciently the articles being treated, and at Vthe'same time is formed so that the barrel is self-unloading upon rotation in one direction.

As set forth hereinabove, the one piece sidewall 42 is made from a sheet of plastic material. A method for forming this sidewall is illustrated in Figs. 2 and 3. By referring to these figures, it will be seen that a mold 102 is provided having a plurality of angularly disposed sides 104, `106, and 108. Longitudinally extending blocks l110, 112, and 114 are disposed centrally `of these sides of the mold for the purpose described below. A wing 116, which conforms to the shape of rthe sidewall sections 54, 56, and 58 described above, is pivotally mounted to one side of the mold, as at 118, and another wing 120, Lwhich conforms to the curved section 52 of the barrel sidewall, ispivotally mounted to an opposite side of the mold, as at y12.2. Elongated abutment members 124 and 126 are secured to the free edges of the wings 116 'andi-120, respectively, vfor engagement with the edges of the sidewall blank in the manner illustrated.

When it is desired to form a sheet of plastic material into a sidewall 42, the sheet is first heated in any well known manner until it becomes pliable. 'Ihe sheet is then placed into the mold 1112 in the manner illustrated in Fig. 2 with the edges of the sheet hooked behind the abutments 124 and .126 on the open wings. The wings are then closed manually, or by suitable means, not shown, tothe position illustrated in Fig. 3. During this movement of the wings, the abutments y124 and 126 apply forces directed transversely of the width of the sheet, which forces cause the sheet to conform to the shape of the mold. The above mentioned blocks through 114 bend the sheet in order to provide the angularly disposed panels with the inclined sections described above. After the wings of the mold have been closed, the plastic sheet is cooled, whereupon the shaped one piece sidewall 42 is removed from the mold and secured to the end plates in themanner described above. The sidewall 42 .is then perforated, as by drillin y a plurality of holes at 128 therein, in order to permit lfree circulation of the plating bath through 'the barrel. Ifl desired, the sidewall may be perforated before it is secured to the end plates, and in some instances, the `plastic sheet may be perforated before it is'placed in the mold.

Figs. ll through 14 illustrate an appara-tus in which the above described article treating unit 16 may be used for carrying out the entire treating or plating operation automatically. This apparatus includes an'endless and preferably generally oval-shaped track 1130 for movably supporting a carriage 132, which carriage has means thereon for raising and lowering Vthe plating unit 16 to immerse the tumbling barrel in a suitable platingwtank 134. Suitable means described hereinbelow are nprovided for intermittently moving the carriage 132 kfrom a barrel loading station to one or more article treating stations and thence to a Ebarrel unloading station and for actuating-'the barrel raising and lowering means and the barrel rotating kmeans in timed relationship with each other andwiththe carriage moving means. With'this arrangement, it will be seen that the barrel may be loaded, and the subsequent treating and unloading operations are carried outautomatically. A

As shown best in Fig. l2, the endless track may comprise a pair of oppositely facing ,channelmembers 136 and 138. The carriagek 132, `which may have'fany suitable structure, is movably supported on thetrack by ,ro11ers .1,40, and 142 .rotatablymounted on an axle144 or Y;

I secured to the carriage frame by suitable means. As

illustrated in Fig. 11, the carriage is preferably supported .by pairs of rollers disposed adjacent leading and trailing ends thereof. The article treating unit 16 is connected with the carriage for vertical adjustment by means of a cable 146 wound on a drum 148 rotatably mounted on the carriage. A reversible electric motor 150 is connected with the drum through a suitable reduction gear box 152 for raising and lowering the article treating unit. Y p v In order to move the carriage 132 around the track, an endless chain 154 encircles the inner track channel member 138 and is connected with the inner end of the carriage supporting axle 144 by any suitable means. A driving sprocket wheel 156 projects through a suitable opening in the channel member 138 for meshing engagement with the chain, and an idler sprocket wheel 158 disposed at the opposite end of the track also projects through an opening in the channel member 138 and meshes with the chain. `Ari electric motor 160 is provided for driving the sprocket wheel 156 and is operatively connected thereto by meshing bevelled gears 162 'and 164 secured,jrpectively, to the motor shaft 166 and the sprocketwheel shaft 168.

l The motor 28 for rotating the article treating or plating barrel, the motor 150 for raising or lowering the barrel, and the motor 160 for driving the carriage along the track are intermittently operated by the means somewhat schematically shown in Figs. 11, 12, and 13. This means includes a pair o f electric conduits 170 and 172 which are connected between a switch box 174 mounted on the track channel member 136 and any suitablel source of power. A master switch 176 is inserted in the line 170 'rto control star-ting and stopping of the apparatus. A pair of electric lines 178 and 180 connect the switch box .174 with the electric motor 160. The switch box 174 is preferably constructed so that the circuit to the motor 160 is normally closed when the master switch is closed,

lwhereupon the motor 160 is energized to advance the carriage 132. A This advancement continues until the carriage 132-reaches an article treating position above the '-plating tank 134, whereupon the mechanism within the switch box 134 is actuated to break the circuit and stop they motor 160. In order to break 4the circuit at the vproper moment, the switch box 134 is preferably distreating or plating ofthe articles in the barrel, the motor 160 is again Venergized to advance the carriage, and this may be accomplished by a suitable timing device in the 'switch box 174 which is energized when the arm 182 is actuated and is adapted to close the switch after the passage of a predetermined interval of time.

-In order to energize the motors 28 and 150, a pair of endless electrical contact strips 186 and 188 are disposed around the track channel member 136 and are -insulated therefrom and from each other by suitable means. v The contact strips are connected with the main power lines by suitable branch lines 190 and 192. As shown best in Fig. 13, a pair of electrical contact brushes 194 and 196 are slidably mounted in a suitable bore in the end of the carriage supporting axle 144 for contact with 'the strips 186 and 188, respectively. Preferably, the brushes are resiliently urged toward the strips by a suitable spring 198 which is insulated from the brushes by a washer 200 of insulating material. A pair of insulated Awires 202 and 204 connect the brushes with a switch box 206 mounted on the platform or frame 18 bede-r connected Vwith the motor 150 by a pair of wires 208 and 210 and with the moto-r 28 by a pair of wires 212 and214.

, The switch box 206 includes a switch mechanism having an operating arm 215 actuated by a suitable cam, not shown, disposed adjacent the path of travel of the unit 16 and at the treating station to close the switch and energize the motor 150, whereby the motor is rotated in a direction to lower the unit 16. Thus, when the carriage 132 reaches the treating station above the tank 134, the motor 150 is immediately energized so as to lower the unit 116. The switch box 206 includes a push buttontype switch actuated by a spring biased plunger 216 which is positioned to engage a plate 218 secured to the upper edge of the tank 134 when the barrel has reached a lower position immersed in the tank. When the plunger 216 is actuated by engagement lwith the plate 218, the motor 150V is de-energized to `stop the downward movej ment of the article treating unit. The switch box 206 also lcontains a switch operated by a timing device for closing the circuit to the motor 150 in a manner to cause reverse rotation of the motor and, thus, raising of the article treating unit. This timing device is preferably energized upon -actuation of the plunger 216 and may be set so that the article plating barrel remains immersed in the plating b'ath for the desired interval of time before being lifted from'the barrel. It is understood, of course, that this timing device must be set to raise the barrel before the above described timing device energizes the motor 160to advance the carriage 132 and the barrel along the track.

The above mentioned switch box 206 also contains a switch mechanism for controlling the operation of the barrel rotating motor 28. This mechanism includes a simple push button-type switch actuated by a plunger 220 which engages the plate 218 on the tank 134 when the barrel is immersed in the tank. Thus, when the unit i 16 reaches its lowered position, the plunger 220 is actuated to close a'switch so that the motor 28 is energized to rotate the plating barrel in the direction indicated by the arrow 60 (see Fig. 7), whereby the articles in the barrel are tumbled for uniform treatment or plating. It

is understood that as the unit 16 is raised from the plating bath, the plunger 220 and the switch actuated thereby return to their normal positions to stop the motor 28.

Yand an unloading station 228.

As is well known, an article to be plated is often coated with several different metals, whereby a plurality of plating baths are required. Thus, in the schematic illustration of Fig. 14, a pair of article treating stations 222 and 224 are shown along with an article loading station 226 In order to unload the articles from the barrel at rthe unloading station, it is merely necessary to rotate the barrel in a direction opposite the arrow '60 (see Fig. 7) and in the manner illustrated by the arrow in Fig. 5. When the barrel reaches the unloading station, `the motor 28 is energized to rotate the barrel in the proper direction by means of suitable switch mechanism in the switch box 206, which switch mechanism is actuated by an arm 230 engageable with fixed cam means (not shown) disposed adjacent the unloading station.

From the above description, the operation of the apparatus is believed to be clear, but a short description of such operation is as follows. Preferably, an article treating unit 16 and carriage mechanism therefor is provided for each work station around the endless track. Thus,

or suitable control means, not shown, may be provided 'for automatically'loading the articles. After the varticles have been loaded, master switch 176 is closed so that the loaded article treating unit 16 is conveyed by the carriage 132 to the treating station 222. When the loaded unit 16 reaches this treating station, the conveyor motor 160 is de-energized by the mechanism in the above described switch box 174, and the motor 150 is energized in the manner described above for lowering the barrel into the plating bath. At the same time, another treating unit has been moved into position at the article loading station and is loaded with articles. After a predetermined intcrval of time, controlled by the timing device in switch box 206, the barrel is raised from the plating bath, whereupon the timing device in switch box 174 is effective to energize the motor 160 until the next article treating unit reaches the treating station 222. It is understood that this operation is carried on continuously, and each article treating unit is advanced to each treating station and to the unloading station 228, where the barrel is rotated in a direction to discharge the articles therefrom. Any suitable means, such as endless conveyor, hopper, or a chute may be provided vfor receiving articles from the barrel at the discharge station. From the discharge station, the barrels are again advanced to the loading station to repeat the cycle of operation.

Referring again briey to the barrel structure, there is provided a discrete and relatively large pocket defined between wall portions 42, 54, S6 and 58, and this pocket may occupy a substantial portion of the left-hand quadrant of the barrel, as viewed in Fig. 7. The .angular tumbling panels 46, 48, 50 extend over a substantial portion of the periphery of the barrel and approximate to a greater or less extent substantially half the barrel Iperiphery. These tumbling panels are along an intermediate portion of the periphery of the barrel and ktend `to eiect increased tumbling action of the articles along lthis portion of the barrel. With such increased tumbling action, and the relatively large outlet openingthe barrel structure is such as to prevent articles from bounc- Iin-g out of the opening without making the opening of fsuch a minute size as to prevent free egress of the treated 'articles when the barrel is rotated in the dumping directionr To this end, the pocket presents a substantially smooth interior wall surface along the arcuate section 54, the curved section 56, and the substantially radial portion 58 so that the previous increased agitation of the articles is reduced as the articles are collected inthe pocket and then discharged therefrom to the opposite angular tumbling panels for further treatment as the barrel is rotated in the treating direction of the arrow 60 in Fig. 7. Thus, the articles in the pocket will tend lto slide along the smooth surface thereof with reduced turbulence so that the tendency for the articles to bounce out 'of the opening is substantially eliminated. Further, positioning of the portion 58 relatively close to the axis of the barrel provides a relatively wide space between it and the arcuate section 52 so as to facilitate substantially free flow of the treated articles therebetween and dump- Iing of the treated articles through the opening 40 when the barrel is rotated in the reverse or dumping direction. ,As illustrated, the end of the wall portion`58 is located 4closer to the axis of the barrel than to the free edge of the arcuate section 52 but this positioning may be varied vwithin limits such as to obtain the desired characteristics tof operation of the barrel during its rotation in the treating direction and its reverse rotation in the dumping di- .rection From the above description, it is seen that the present vinvention has provided a novel article treating unit having `self-contained means for rotating the barrel, whereby the unit may be used with various plating baths without requiring setting up any complicated drive mechanism. Furthermore, it is seen that the present invention has l provided a novel article treating or plating barrel' which may be quickly and easily either loaded or unloaded and whicl is capable of efliciently tumbling 'articles'therein to insure uniform treatment ofthe articles. More specically, it is seen that the present invention has provided a novel barrel of simple and economical construction while at the same time highly eflicientin operation. In addition, it is seen that the present invention has provided a relatively simple apparatus including a'novel self-unloading barrel, whereby various steps of the plating oph eration may be carried out substantially automatically and, therefore, relatively quickly and economically.

This application is a continuation of my co-pending application, Serial Number 373,136, filed August 10, 1953, now abandoned, entitled, Apparatus for Plating Articles and Method 4for Making Same.

While the preferred embodiment of the present invention has been shown and described herein, it is obvious that many structural details maybe changed without departing from the spirit and scope of the appended claims.

The invention is claimed as follows:

l. In an apparatus for treating articles, ,a barrel cornprising end walls and a one piece plastic sidewall, said sidewall including longitudinally extending arcuate sections spaced from one another to provide an article inlet and outlet opening and forming substantially approximately half the periphery of the barrel and said sidewall further including a plurality of angularly disposed tumbling panels between said arcuate sections and substantially completing the remaining periphery of the barrel, said arcuate sections terminating in free marginal portions, one of said marginal portions being located substantially inwardly from the other marginal portion toward .the axis of the barrel and providing with the contiguous arcuate section a discrete substantially radial pocket with a generally smooth gradually curved surface merging with the adjacent tumbling panel Vand operating to trap with reduced agitation articles accumulating therein from the angularly disposed tumbling panels when the barrel is rotating in the treating direction whereby to prevent articles from bouncing out of the barrel through the space between the said marginal portions.

2. In an apparatus for treating articles as claimed in claim 1, wherein the marginal portions are disposed in radially overlapping relationship, and wherein said one marginal portion extends inwardly of the barrel `from substantially the midportion of one quadrant of the barrel adjacent said opening.

3. In an apparatus as claimed in claim l, wherein at least some of said angularly disposed panels have midportions thereof projecting inwardly of the barrel to increase tumbling action on the articles passing therealong.

4. In an apparatus for treating articles, a barrel adapted for rotation in an article treating direction and for opposite rotation in an article dumping direction and comprising a one piece plastic sidewall, said sidewall including longitudinally extending arcuate'sections spaced from one another to provide an article Ainlet and outlet opening through the barrel periphery and forming substantially approximately half the periphery of the barrel and said sidewall further including a plurality of angularly disposed tumbling panels between said arcuate sections and substantially completing the remaining periphery of the barrel, said arcuate sections terminating in lfree marginal portions, one of said marginal portions terminating substantially inwardly from the freeedge of the other marginal portion toward the axis of the barrel to provide an enlarged egress passage for articles when the barrel is rotating in the dumping direction and providing with the contiguous arcuate Section a discrete and relatively deep substantially radial pocket with predominantly smooth inner surfaces merging with the adjacent tumbling panel operating to reduce agitation of articles accumulating therein from the -angularly disposed tumbling panels when the barrel is rotating in the treating direction whereby to prevent articles from bouncing out of the barrel through the said egress passage as the articles pass from the pocket to the angularly disposed tumbling panels for further treatment while the barrel is rotating in the treating direction.

5. In an apparatus for treating articles as claimed in claim 4, wherein the inwardly directed marginal portion merges into the contiguous arcuate section along a curved inner surface effective to reduce agitation of articles passing therebetween as the barrel is rotated in the treating direction.

6. In an apparatus for treating articles as claimed in claim 4, wherein the inwardly directed marginal portion has the free edge thereof terminating relatively closer to the axis of rotation of the barrel than to the free edge of the other marginal portion.

7. In an apparatus for treating articles, a barrel comprising end walls and a sidewall having a plurality of angularly disposed tumbling panels forming substantially approximately half the periphery of the barrel for eiecting relatively turbulent tumbling action therealong and a pair of arcuate end sections included in the remaining periphery of the barrel, the terminal edge of a rst arcuate section being spaced circumferentially from the other arcuate section to leave an opening through the periphery of the barrel, said arcuate sections and said opening covering the complemental periphery of the barrel, the second arcuate section terminating in a curved section merging into a substantially radial portion extending inwardly of the barrel to a point substantially inwardly of said rst arcuate section and relatively close to the axis of rotation of the barrel and providing with said second arcuate section and said curved section a discrete and relatively deep substantially radial pocket along a fraction of the periphery of the barrel with substantially smooth interior Wall surfaces merging with the adjacent tumbling panel whereby to prevent the articles being treated from bouncing out of the pocket as the barrel is inverted during rotation thereof in the treating direction, and said rst arcuate section being relatively widely spaced from said substantially radial portion to facilitate egress of articles therebetween and discharge through said opening as the barrel is rotated in the opposite dumping direction. i

8. In an apparatus for treating articles as claimed in claim 7, wherein the substantially radial portion comprises an elongated section with the terminal edge thereof located relatively closer to the axis of rotation of the barrel than to said first arcuate section.

10 9. In an apparatus for treating articles, a barrel adapted for rotation in an article treating direction and for opposite rotation in an article dumping direction and comprising end walls and a sidewall having a plurality of angularly disposed tumbling panels substantially approximating half the periphery of the barrel for effecting relatively turbulent tumbling action therealong, the said intermediate portion of the periphery of the barrel terminating in a pair of arcuate end sections spaced from one another to provide an inlet and outlet opening and forming with said opening the remaining complemental periphery of the barrel, one of said arcuate end sections terminating in an inwardly directed wall portion extending toward a tumbling panel remote from the aforesaid one arcuate section and lapping the edge of the other arcuate end section in spaced relation thereto at a position disposed relatively close to the axis of rotation of the barrel and substantially radially opposing the tumbling panel adjacent the aforesaid one arcuate section, the said inwardly directed portion and contiguous arcuate end section forming a discrete and relatively deep radial pocket with predominantly smooth interior surfaces merging with the adjacent tumbling panel to trap with reduced agitation articles accumulating therein from the tumbling panels as the barrel is rotated in the treating direction, the inner edge of said inwardly directed portion being positioned with respect to the peripheral extent of the barrel including the tumbling panels so as to substantially prevent any articles engaged by any turnbling panel from gaining access to the said opening as the barrel is rotated in the treating direction.

References Cited in the tile of this patent UNITED STATES PATENTS 2,491,925 Lazaro Dec. 20, 1949 2,562,084 Collick July 24, 1951 2,640,025 Lazaro May 26, 1953 2,741,463 Colclesser Apr. 10, 1956 2,749,572 Nowak June 12, 1956 ,2,762,772 Jackson Sept. 11, 1956 2,777,165 Hurt Jan. 15, 1957 2,836,400 i Jackson May 27, 1958 FOREIGN PATENTS 464,334 Italy July 28, 1951 

1. IN AN APPARATUS FOR TREATING ARTICLES, A BARREL COMPRISING END WALLS AND A ONE PIECE PLASTIC SIDEWALL, SAID SIDEWALL INCLUDING LONGITUDINALLY EXTENDING ARCUATE SECTIONS SPACED FROM ONE ANOTHER TO PROVIDE AN ARTICLE INLET AND OUTLET OPENING AND FORMING SUBSTANTIALLY APPROXIMATELY HALF THE PERIPHERY OF THE BARREL AND SAID SIDEWALL FURTHER INCLUDING A PLURALITY OF ANGULARLY DISPOSED TUMBLING PANELS BETWEEN SAID ARCUATE SECTIONS AND SUBSTANTIALLY COMPLETING THE REMAINING PERIPHERY OF THE BARREL, AND ARCUATE SECTIONS TERMINATING IN FREE MARGINAL PORTIONS, ONE OF SAID MARGINAL PORTIONS BEING LOCATED SUBSTANTIALLY INWARDLY FROM THE OTHER MARGINAL PORTION TOWARD THE AXIS OF THE BARREL AND PROVIDING WITH THE CONTIGUOUS ARCUATE SECTION A DISCRETE SUBSTANTIALLY RADIAL POCKET WITH A GENERALLY SMOOTH GRADUALLY CURVED SURFACE MERGING WITH THE ADJACENT TUMBLING PANEL AND OPERATING TO TRAP WITH REDUCED AGITATION ARTICLES ACCUMULATING THEREIN FROM THE ANGULARLY DISPOSED TUMBLING PANELS WHEN THE BARREL IS ROTATING IN THE TREATING DIRECTION WHEREBY TO PREVENT ARTICLES FROM THE BOUNCING OUT OF THE BARREL THROUGH THE SPACE BETWEEN THE SAID MARGINAL PORTIONS. 